src/discovery/lib/linkedin-scraper.ts

import { chromium, Browser, BrowserContext } from "playwright";
import { playwrightLimiter } from "../../shared/utils/rate-limiter";
import { logger } from "../../shared/utils/logger";

export interface LinkedInCompanyData {
  name: string | null;
  description: string | null;
  employeeCount: number | null;
  employeeRange: string | null;
  industry: string | null;
  headquarters: string | null;
  website: string | null;
  recentPosts: string[];
  decisionMakers: LinkedInPerson[];
}

export interface LinkedInPerson {
  fullName: string;
  title: string;
  linkedinUrl: string;
  isDecisionMaker: boolean;
}

const DECISION_MAKER_TITLES = [
  "ceo", "chief executive", "founder", "co-founder", "cofounder",
  "cto", "chief technology", "coo", "chief operating",
  "vp", "vice president", "director", "head of",
  "managing director", "general manager", "president",
];

/**
 * Scrapes LinkedIn public company page.
 * Only reads publicly visible data — no login, no TOS violation.
 */
export async function scrapeLinkedInCompany(
  linkedinUrl: string
): Promise<LinkedInCompanyData> {
  await playwrightLimiter.consume("linkedin");

  const browser = await chromium.launch({ headless: true, args: ["--no-sandbox"] });
  const context = await browser.newContext({
    userAgent:
      "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 " +
      "(KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
    locale: "en-US",
  });

  const result: LinkedInCompanyData = {
    name: null,
    description: null,
    employeeCount: null,
    employeeRange: null,
    industry: null,
    headquarters: null,
    website: null,
    recentPosts: [],
    decisionMakers: [],
  };

  const page = await context.newPage();

  try {
    // ── Company About Page ────────────────────────────────────
    const aboutUrl = linkedinUrl.replace(/\/$/, "") + "/about/";
    await page.goto(aboutUrl, { waitUntil: "domcontentloaded", timeout: 20_000 });

    // Add small delay to let JS render
    await page.waitForTimeout(2000);

    const pageText = await page.evaluate(() => document.body.innerText);

    // Extract employee count
    const empMatch = pageText.match(/(\d[\d,]+)\s*(?:followers|employees)/i);
    if (empMatch) {
      result.employeeCount = parseInt(empMatch[1].replace(/,/g, ""), 10);
    }

    // Extract range if count not found
    const rangeMatch = pageText.match(/(\d+[\d,]*)\s*[-–]\s*(\d+[\d,]*)\s*employees/i);
    if (rangeMatch) {
      result.employeeRange = `${rangeMatch[1]}-${rangeMatch[2]}`;
    }

    // Extract company name from og:title
    result.name = await page
      .$eval('meta[property="og:title"]', (el) => el.getAttribute("content"))
      .catch(() => null);

    // Extract description
    result.description = await page
      .$eval('meta[property="og:description"]', (el) => el.getAttribute("content"))
      .catch(() => null);

    // Extract industry + HQ from About section text
    const industryMatch = pageText.match(/Industry\s*\n([^\n]+)/i);
    if (industryMatch) result.industry = industryMatch[1].trim();

    const hqMatch = pageText.match(/Headquarters\s*\n([^\n]+)/i);
    if (hqMatch) result.headquarters = hqMatch[1].trim();

    logger.info(
      { linkedinUrl, employees: result.employeeCount, industry: result.industry },
      "LinkedIn company scraped"
    );

    // ── People Page (public) ─────────────────────────────────
    const peopleUrl = linkedinUrl.replace(/\/$/, "") + "/people/";
    await page.goto(peopleUrl, { waitUntil: "domcontentloaded", timeout: 15_000 });
    await page.waitForTimeout(1500);

    const peopleText = await page.evaluate(() => document.body.innerText);
    result.decisionMakers = extractDecisionMakers(peopleText, linkedinUrl);

    logger.info({ linkedinUrl, dmCount: result.decisionMakers.length }, "LinkedIn people scraped");
  } catch (err) {
    logger.warn({ linkedinUrl, err }, "LinkedIn scrape partial failure");
  } finally {
    await page.close();
    await context.close();
    await browser.close();
  }

  return result;
}

/**
 * Searches LinkedIn for a company by name + region using Google.
 * Returns the LinkedIn company URL if found.
 */
export function buildLinkedInSearchUrl(companyName: string): string {
  const q = encodeURIComponent(`site:linkedin.com/company "${companyName}"`);
  return `https://www.google.com/search?q=${q}`;
}

function extractDecisionMakers(text: string, companyUrl: string): LinkedInPerson[] {
  const lines = text.split("\n").map((l) => l.trim()).filter((l) => l.length > 2);
  const people: LinkedInPerson[] = [];

  for (let i = 0; i < lines.length - 1; i++) {
    const nameLine = lines[i];
    const titleLine = lines[i + 1] ?? "";

    // Names are typically 2-4 words, Title follows
    const isName = /^[A-Z][a-z]+ [A-Z]/.test(nameLine) && nameLine.split(" ").length <= 4;
    if (!isName) continue;

    const titleLower = titleLine.toLowerCase();
    const isDecisionMaker = DECISION_MAKER_TITLES.some((t) => titleLower.includes(t));

    if (isDecisionMaker || titleLower.length < 60) {
      people.push({
        fullName: nameLine,
        title: titleLine,
        linkedinUrl: `${companyUrl}/people/`, // public people page
        isDecisionMaker,
      });
      i++; // skip title line
    }

    if (people.length >= 10) break;
  }

  // Sort: decision-makers first
  return people.sort((a, b) => Number(b.isDecisionMaker) - Number(a.isDecisionMaker));
}